I know about the greatness of MLS gaskets. I have used the Mitsu MLS before. The perma-torque is great, I know.
I already checked the block for flatness, it appears to have a .002" variance which should be within spec.
ARP does not manufacture 6-bolt L19s anymore.
A1/Map and a Mitsu or Fel-Pro MLS.
Then Bye Bye car!
